Pb²⁺ and Hg²⁺ removal from polluted milk by di-acrylated Pluronic P123 hydrogels

Milk is often polluted by heavy metal ions due to the growing environment pollution, but few methods have been developed to remove the heavy metal ions. Here a non-toxic sorbent, namely di-acrylated Pluronic P123 (P123-DA) hydrogel, was fabricated for removal of Hg²⁺ and Pb²⁺ from milk without impairing their nutritive contents. This hydrogel possessed high mechanical stress and maximum adsorption capacity of 35.2 and 53.9 mg/g for Pb²⁺ and Hg²⁺. The removal ratio of Pb²⁺ and Hg²⁺ by P123-DA hydrogel respectively reached 85.3% and 81.9% for the polluted whole milk while was individually 86.3% and 83.8% for the skim milk. Interestingly, the treatment by P123-DA hydrogel didn't significantly reduce the main nutritive contents in milk. Such hydrogel will be a recyclable, safe and effective tool for reuse of milk that polluted by heavy metal ions.